DataSheet_1_Heterogeneity of tumor immune microenvironment and real-world analysis of immunotherapy efficacy in lung adenosquamous carcinoma.docx

Lung adenosquamous carcinoma (ASC) is an uncommon histological subtype. We aimed to characterize the tumor immune microenvironment (TIME) in lung ASC and estimate patient response to immune checkpoint inhibitors (ICIs), which have never been systematically investigated. In cohort I, we collected 30 ASCs from a single center for analysis of TIME characteristics, including immuno-phenotyping, tumor mutation burden (TMB), T-cell receptor (TCR) repertoires, tumor-infiltrating lymphocytes (TILs), and immune checkpoint expression. Twenty-two (73.3%) patients were EGFR-positive. The TIME was defined by immune-excluded (60%) and immune-desert phenotype (40%). Strikingly, programmed cell death-ligand 1 (PD-L1) and programmed cell death-1 (PD-1) were predominantly expressed in squamous cell carcinoma components (SCCCs) versus adenocarcinoma components (ACCs), where enhanced CD4+ FOXP3+ regulatory T cell and attenuated CD57+ natural killer cell infiltration were present, consistent with a landscape of fewer innate immune cells, more immunosuppressive cells. SCCCs had higher TMB, higher TCR clonality, and lower TCR diversity than ACC. In cohort III, the efficacy of ICI-based therapy was estimated using a real-world data of 46 ASCs from 11 centers. Majority of 46 patients were driver genes negative and unknown mutation status, 18 (39%) and 18 (39%), respectively. The overall objective response rate of 28%, median progression-free survival of 6.0 months (95% confidence interval [CI] 4.3–7.7), and median overall survival of 24.7 months (95% CI 7.2–42.2) were observed in the ICI-based treatment. This work ascertains suppressive TIME in lung ASC and genetic and immuno-heterogeneity between ACCs and SCCCs. Lung ASC patients have a moderate response to ICI-based immunotherapy.

肺腺鳞癌（Lung adenosquamous carcinoma, ASC）是一种少见的组织学亚型。本研究旨在解析肺ASC的肿瘤免疫微环境（tumor immune microenvironment, TIME），并评估患者对免疫检查点抑制剂（immune checkpoint inhibitors, ICIs）的应答情况，这一研究主题此前尚未得到系统性探索。
在队列I中，我们从单中心收集了30例ASC样本，用于分析TIME特征，包括免疫表型分型、肿瘤突变负荷（tumor mutation burden, TMB）、T细胞受体（T-cell receptor, TCR）库、肿瘤浸润淋巴细胞（tumor-infiltrating lymphocytes, TILs）以及免疫检查点分子表达情况。其中22例（73.3%）患者为EGFR阳性。
该肿瘤的TIME以免疫排斥型（60%）和免疫荒漠型（40%）为主要特征。值得注意的是，程序性死亡受体配体1（programmed cell death-ligand 1, PD-L1）与程序性死亡受体1（programmed cell death-1, PD-1）主要表达于鳞状细胞癌组分（squamous cell carcinoma components, SCCCs），而非腺癌组分（adenocarcinoma components, ACCs）；后者伴随CD4+ FOXP3+调节性T细胞浸润增强，以及CD57+自然杀伤细胞浸润减弱，这与先天免疫细胞占比更低、免疫抑制细胞占比更高的免疫景观相符。
与ACCs相比，SCCCs具有更高的TMB、更高的TCR克隆性以及更低的TCR多样性。
在队列III中，我们通过来自11个中心的46例ASC患者的真实世界数据，评估了基于ICI的治疗方案的疗效。46例患者中绝大多数为驱动基因阴性及突变状态未知者，占比分别为18例（39%）与18例（39%）。接受基于ICI治疗的患者中，总体客观缓解率为28%，中位无进展生存期为6.0个月（95%置信区间[CI] 4.3~7.7），中位总生存期为24.7个月（95%置信区间[CI] 7.2~42.2）。
本研究明确了肺ASC中存在免疫抑制性TIME，以及ACCs与SCCCs之间存在遗传与免疫异质性。肺ASC患者对基于ICI的免疫治疗应答中等。